First came "The Real World" and "Survivor," followed by "The Apprentice," "American Idol," "The Bachelor," "Rock of Love," "Fear Factor," "Dancing with the Stars" and all those "Real Housewives," among dozens of reality TV shows.

And then there's Kim Kardashian. She's a reality TV celebrity, yes, but that's just half the story. What's she's done, and is doing, is leverage her television success into entrepreneurial gold.

The 29-year-old star became a household name after her family signed on to E!'s "Keeping Up With The Kardashians" in 2007. With a ballooning fan base, she quickly became known for her style and sex appeal. It didn't take long for her to transform that notoriety into a strong business brand.

When Kardashian enters, her high heels are followed by a clingy olive mini-dress, a voluminous mane of long black hair and a posse of assistants. "The show is the reason we have the brands," she says carefully, thoughtfully. "The show started it all."

She took stock of what her fans were asking her about — style, diet and beauty tips — and soon launched workout DVDs, an eponymous fragrance line and shoe-shopping Web site, ShoeDazzle. With her sisters Kourtney and Khloe, she also owns and is expanding Dash clothing boutiques, created a clothing line for Bebe and nabbed diet (Quick Trim) and skincare (PerfectSkin) product endorsements.

"I've always been a businesswoman," says Kardashian in a near-child's voice, noting that she worked as a teen with her father, the late attorney Robert Kardashian, best known for defending O.J. Simpson. She believes that the reality TV platform is a powerful marketing tool for her personal brand. "It's our best commercial."

Today the rags-to-reality-star fairy tale is all too common. Unknowns and all-but-has-beens like Kate Gosselin and Bret Michaels agree to be trailed by a camera and somehow shoot onto multiple magazine covers and red carpets.

The untold story is about reality personalities who are able to monetize their TV success by launching profitable businesses, product lines and even media empires that easily outlast their 15 minutes in the spotlight.

Bridging reality TV fame and smart commerce isn't easy, says Mark Stevens, chief executive of marketing firm MSCO and author of "Your Marketing Sucks." "You make a critical transition from artificial reality to the real world," he explains. "It's a shark-filled moat. Quite a few people have been eaten alive."

Those that do make it work have a unique mix of personality, talent, credibility and business sense. On the spectrum of reality television shows — with, say, "Jersey Shore" on the lower end and "American Idol" as the crown jewel — talent-based competition shows like "Project Runway" or "Top Chef" offer contestants instant industry cred and a valuable opportunity to market their work.

"It's really the best business plan," says fashion designer Christian Siriano, the winner of "Runway's" season four. After his title-winning finish in 2008, he was busy making the rounds to talk shows and doing fittings with celebrities like Heidi Klum and Victoria Beckham when he realized how marketable his name had become. "I thought, I need to turn this into a business." he says.

At just 22, Siriano had at least two things going for him: A well-known personality built on catch phrases like "fierce" and "hot tranny mess" and a wealth of design talent. The rest he learned as he went along.

He immediately began working on his first solo collection with a good chunk of the $100,000 prize money, and showed five months later while his name was still in the conversation. He also received multiple contract offers and tackled those that he loved. "I weeded through them," he says, "because let me tell you, I was asked to do some of the tranniest, tackiest things."

In just two years Siriano has shown several times at New York Fashion Week, with sponsors like LG and Sprint, and he sold his Fall 2009 collection to Saks Fifth Avenue. He created a line of shoes and bags for Payless, a makeup line for Victoria's Secret and a clothing collection for Puma. "(Project Runway) was an amazing experience," he says, "but afterward, you really have to take it on your own and keep it going."

"The smart ones will jump on the opportunity quickly with a good, diversified business plan," agrees Adam Kluger, former E! News producer and current president of Adam Kluger Public Relations. "You have to have something that people want."

In order to successfully capitalize on reality TV fame, the celebrity's product or service must tie in to his or her reputation that was built on the show. Kardashian's fragrance line, for example, targeted her audience of young women and fit her persona as a sexy socialite. "But we wouldn't want to buy a Kim Kardashian encyclopedia," quips marketing exec Stevens.

Successful celebreneurs recognize their market. Jillian Michaels, star trainer on NBC's weight-loss reality series "The Biggest Loser," realized this early on. She says she crystallized her professional vision immediately after the first season aired. (It's currently in season nine.) As a fitness specialist on a prime-time network show, she knew she could use that expert status to create and market a robust wellness brand.

Michaels launched products like workout DVDs, fitness-based videogames and books, exercise equipment, diet pills and protein powders. And in 2008 she cofounded Empowered Media to run her brand. "I wanted to hatch a hybrid wellness brand/media company that could merchandise like Omni and produce and manage other wellness brands like Harpo," says Michaels. The move rocketed her retail sales from $20 million to over $100 million in just two years.

Of course, appearing on a reality show can be a risk. "Most of the time it's not good for business," says Richard Laermer, author of 2011: Trend-Spotting and former cohost of TLC's reality show "Taking Care Of Business." "If you go on 'Fear Factor' and are made to look like an idiot, people will say, 'Why hire this guy?'"

Season two "Project Runway" winner Chloe Dao saw this firsthand. While she was able to successfully launch a fashion line for QVC and a line of accessories sold at Target and Office Depot, she says that some of her fellow cast members damaged their reputations on the show. "A few had crying tantrums, and it was harder for them to find fashion jobs afterward," she admits. "Negative press is negative press. It can really hurt you."

But even when a show enhances your personal brand, it doesn't automatically result in business success. Celebrity chef Rocco DiSpirito filmed NBC reality show "The Restaurant" in 2003 about opening his New York City restaurant, Rocco's. Despite the buzz the show garnered, the restaurant was a flop and closed a year later.

"You have to have common sense," says Bill Rancic, entrepreneur and winner of the first season of NBC's "The Apprentice." "A lot of these people get caught up in the fame and become intoxicated by the camera."

Rancic has managed to use his TV celebrity to his advantage, saying that it brought his businesses to the "next level." After selling his multimillion-dollar company Cigars Around The World to Synergy Brands, he remained on the board of directors. He recently negotiated a 20-year licensing deal between Synergy and Food Network chef Paula Deen, an opportunity he says he may not have had without the television exposure. He's also become a popular motivational speaker, published two books and continues to produce new reality shows.